Backshell Radiative Heating on Human-Scale Mars Entry Vehicles

Abstract: This work quantifies the backshell radiative heating experienced by payloads on human- scale vehicles entering the Martian atmosphere. Three underlying configurations were studied: a generic sphere, a sphere-cone forebody with a cylindrical payload, and an ellipsled. Computational fluid dynamics simulations of the flow field and radiation were performed using the LAURA and HARA codes, respectively. Results of this work indicated the primary contributor to radiative heating is emission from th...

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Development of a Multifidelity Approach to Acoustic Liner Impedance Eduction

Abstract: The use of acoustic liners has proven to be extremely effective in reducing aircraft engine fan noise transmission/radiation. However, the introduction of advanced fan designs and shorter engine nacelles has highlighted a need for novel acoustic liner designs that provide increased fan noise reduction over a broader frequency range. To achieve aggressive noise reduction goals, advanced broadband liner designs, such as zone liners and variable impedance liners, will likely depart from conventi...

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Technology Considerations for Inclusion of Survivability in MDAO

Abstract: Rising traffic density, along with autonomy and diversity of vehicles in the air, will fundamentally change the safety environment of the future air transportation system. The change in risk is two-fold: increasing chances of mid-air collisions with non-cooperative objects and increasing chances of crashes over highly populated areas. The changing nature of the vehicles populating the airspace means that civilian aircraft design must now explicitly include considerations of survivability in t...

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Initial Investigation into the Psychoacoustic Properties of Small Unmanned Aerial System Noise

Abstract: For the past several years, researchers at NASA Langley have been engaged in a series of projects to study the degree to which existing facilities and capabilities, originally created for work on full-scale aircraft, are extensible to smaller scales --those of the small unmanned aerial systems (sUAS, also UAVs and, colloquially, `drones') that have been showing up in the nation's airspace of late. This paper follows an e ort that has led to an initial human{subject psychoacoustic test regardi...

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A novel practical test for the function of HDL, the carrier of ‘good’ cholesterol

High-density lipoprotein cholesterol (HDL-C) is known as "good" cholesterol, because HDL particles removes excess cholesterol from arterial walls and transport them back to the liver. A research group has developed a practical test for the ability of HDL to accept cholesterol. This method could help to prevent and monitor cardiovascular disease, and it is simple enough to be used in everyday clinical situations.

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Approach Considerations in Aircraft with High-Lift Propeller Systems

Abstract: NASA's research into distributed electric propulsion (DEP) includes the design and development of the X-57 Maxwell aircraft. This aircraft has two distinct types of DEP: wingtip propellers and high-lift propellers. This paper focuses on the unique opportunities and challenges that the high-lift propellers--i.e., the small diameter propellers distributed upstream of the wing leading edge to augment lift at low speeds--bring to the aircraft performance in approach conditions. Recent changes to ...

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Maxwell’s demon extracts work from quantum measurement

(Phys.org)—Physicists have proposed a new type of Maxwell's demon—the hypothetical agent that extracts work from a system by decreasing the system's entropy—in which the demon can extract work just by making a measurement, by taking advantage of quantum fluctuations and quantum superposition.

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